A federal judge on Friday ordered the city of Yakima to change its elections system to comply with the Voting Rights Act, finding that Latinos do not have full participation in City Council races.

Judge Thomas Rice’s summary judgment came after the Washington chapter of the American Civil Liberties Union (ACLU) sued Yakima in 2012. The organization argues that the city’s at-large elections dilute the Latino vote and block representation despite the minority group making up a third of the city’s voting-age population. The lawsuit was part of a protracted effort to change the city’s election system.

“In the final analysis, there is only one rational conclusion to be drawn from the undisputed evidence recounted above: that the non-Latino majority in Yakima routinely suffocates the voting preferences of the Latino minority,” Rice wrote. “In reaching this conclusion, the Court does not mean to suggest that non-Latinos are deliberately conspiring to outvote their Latino colleagues, or that the City has engaged in any wrongdoing.”

The case marks the first of its kind in Washington state, but the ACLU has successfully challenged at-large voting systems in communities elsewhere.

Forty-one percent of Yakima’s more than 91,000 residents are Hispanic, but the city has never elected a Hispanic member to its at-large City Council. Yakima has four council members who represent districts and three at-large members, but the district candidates are selected only in primary elections. Every resident casts votes for each council seat in the general election.

The ACLU has been pushing the city to change its system since 2010. In 2011, council members refused to put an initiative on a special ballot requiring that the seven members each represent a specific district, and Yakima voters defeated an initiative to change the system in last year’s primary.

Francis Floyd, a Seattle attorney representing the city, said the judgment was “disappointing,” but he declined to comment further, adding that the city is looking at its options.

City Manager Tony O’Rourke told the Yakima Herald-Republic that the City Council will decide whether it will appeal. The next City Council election is scheduled for next year.

Rice directed the city to work with the ACLU to come up with a remedial districting plan.

The most recent example used by advocates to illustrate the shortfalls of the election system was a 2013 Yakima School Board race in which a woman with a Latino name lost, 60 to 40 percent, to a woman who was not campaigning and had dropped out of the race.

“The Latino community in Yakima now will have a chance for their interests to be represented on the City Council,” Kathleen Taylor, ACLU of Washington’s executive director, said in a statement. “Latino voters will be able to elect a candidate of their choice and to have more of a say in how city services are distributed. All voices of the community need to be represented in local government — that’s what democracy is all about.”